Dust flux, Vostok ice core

Two dimensional phase space reconstruction of dust flux from the Vostok core over the period 186-4 ka using the time derivative method. Dust flux on the x-axis, rate of change is on the y-axis. From Gipp (2001).

Tuesday, February 9, 2016

A little stratigraphic correlation

The sidewalks in Guilin are paved with fossiliferous shales.

Bryozoa

Gastropod. Part of my shoe for scale.

More bryozoa (bottom), a gastropod (centre, top), and an orthoceratid (upper left), which is a kind of cephalopod.

A large orthoceratid, and at least one brachiopod.

A rugose coral (also called a horn coral).

Various crinoid ossicles (echinoderms).

A tabulate coral. I had found a better example, but can't find the photo (or maybe it was blurred and deleted).

A couple of brachiopods, with the section cut through both valves, plus assorted fossil debris.

What is interesting to me is how similar this collection of organisms is to that of Devonian sediments near Port Colborne, Ontario.

Actually, the following photos are from various sites near where I have described--but some of these are nearly 30 years old (from slides) so I may not really remember where they are from.

Rugose corals from the Port Colborne quarry.

A tabulate coral from the Port Colborne quarry.

These fossils are Devonian in age, and more closely resemble the corals in Guilin than other corals from my image collections of Ordovician age. The other fossils don't (to my unpracticed eye) seem to have changed much over the same interval.

I asked one of the locals where the sidewalk tiles come from. She claimed that they were quarried nearby, but not from any of Guilin's famous dragon's teeth. Although I did notice quarries on a few of them.

2 comments:

Hello, my name is Annette and I have found many fossils from the Devonian period in my mother's yard in Port Colborne, Ontario. Do you have any idea if they came from the earth and rock quarried to build the canal? I can't seem to find any answers online about this issue.

Without knowing more about the ground on which your mother's house is built, it is hard to be sure. But many of the rocks around Port Colborne will have these fossils, so it is possible that the ground was leveled before the subdivision was built. The developers may have had to crush rock outcrops, or possibly fill in holes with gravel and cobbles. Either way could also leave you with fossil stones in your yard.